#BODY Page 27
WHAT’S THE TIME, MR WOLF?
It’s cheaper than a Rolex and doesn’t need winding up. It’s your internal clock – your very own way of telling the time. Complexity Guru Ross Harper insists that keeping your clock in sync is essential for healthy living, yet is surprisingly difficult to do in the modern world.
What is the time? It’s an interesting question. Toddlers struggle with it, latecomers avoid it, and the wealthy throw their money on jeweled accessories to answer it. Whatever the case, we all tend to agree: to know the time, we need to check the time. But it turns out this isn’t quite true. We each have an internal clock that guides our biology according to a daily schedule. So, while Mr. Wolf may not be able to answer the question, it turns out his body already has. Problems arise, however, when the clock fails… When I say internal clock, I’m not referring to the toy watch you found in your Christmas stocking one year and then subsequently swallowed in all the excitement (though I concede, that too qualifies as an internal clock). Rather, I’m talking about the ability for individual cells to keep time. Just as a typical watch synchronizes it’s ticking to the vibrations of a quartz crystal, so your cells regulate themselves using fluctuations in the levels of specific ‘clock’ proteins. It’s a miniature molecular cascade that lasts roughly 24 hours, and at the end of it all, another day is done – hence why we call it ‘circadian’, from the Latin, circa (about) and diem (a day).
Nature’s dodgy clock
Now as a budding young biologist, I’m a firm believer in the wisdom of Nature. But on this occasion, I’m afraid our circadian clock can’t quite contend with the likes of Rolex or Breitling. The fact is, we’re a little slow. Fortunately, our clocks are constantly re-calibrated by environmental cues – most notably, that heliocentric horologist we call the ‘Sun’. And it’s all thanks to some intricate inner workings that would rival the finest Swiss timepiece. The main circadian regulator in humans is made up of around 1000 nerve cells and is located just behind our eyes in a part of the brain called the ‘Supra Chiasmatic Nucleus’ (taken straight from Webster’s collection of snappy names). Every morning, sunlight enters our eyes and resets the clock – thanks to the breakdown of a rather amicably named clock protein, ‘ TIM’. In this way, dawn marks the beginning of a 24-hour cycle in which we wake, eat, work, eat, surf the Internet for pictures of cats, eat, and finally sleep. Or at least that’s how things were supposed to work before Thomas Edison had the bright idea of trapping light inside a glass bulb. Now our clocks rarely get a proper daily reset.
In today’s world, we are constantly bathed in the glow of artificial light. We are never far from the glare of a computer screen, the hum of a halogen lamp, or the blinking of a thousand LED eyes on the various appliances that populate our homes. Aside from being a nuisance – I’ve long since given up on trying to see the stars through a thick layer of light pollution – this luminescent onslaught also affects our circadian clock. What time is it? Our bodies are becoming less sure of the answer. And this uncertainty brings some pretty dire consequences. Sleep disorders are common, but more frightening is that circadian disruption can lead to cancer, diabetes, and a myriad of mental health problems. (Quick! Someone get me a Rolex! No? Fine, an egg timer will do!) Thankfully, just 135 years post-Edison, we are now clocking on to the importance of circadian well-being. The human eye contains around 100 million light-detecting cells, most of which are necessary for vision. However, a small subgroup is used to relay information to our circadian clock about the light around us. Interestingly, these cells happen to be particularly sensitive to blue light. So, by stopping artificial sources of blue light from getting into the eye, the idea is that we could pull an all-nighter at the computer without confusing our circadian clock. (It’s as if the clock can only ‘see’ in blue, and so by filtering out this colour, we trick it into thinking it’s actually dark – when we’re really just staying up past our bedtime). It’s hard to believe our brain might be that gullible; indeed, the reality is likely to be a bit more complicated. But this idea of filtering out blue light seems to be doing the trick: in clinical tests, special blue light-blocking goggles worn three hours before bed were shown to improve mood and sleep quality. While the same effect has yet to be seen for the other, more sinister symptoms of circadian disturbance, it’s a promising start. And the U.S. military seems convinced, even if you’re not. The Department of Defense are already prototyping their own circadian goggles in the hopes of crafting stronger, faster soldiers. Now to a guy like me, a pair of socially acceptable RoboCop-esque goggles sounds like a dream come true. But I appreciate this may not be the case for the more conservative circadian health enthusiast. A simpler approach would therefore be to outsource the job to your laptop or smartphone; software is already available that can alter the brightness and colour of an electronic display to better match the type of light we should be experiencing for the time of day. How do I know? Well, it’s 11 o’clock in the evening, and I’m typing these words in the warmth of a deep orange computer screen. (Though I am still feeling a little sleepy…. Perhaps another coffee?) A bit late in the day, perhaps, but 2014 looks set to usher in a heightened awareness of the importance of a healthy biological schedule. It might not be all that long before we look back on our current lifestyle with the same sense of “well, duh!” that we give to asbestos in classrooms and makeup products containing lead. Whatever the case, perhaps we might offer a bit more thought to a question we hear daily. What is the time? You should already know.
A biologist straight out of Cambridge University, Ross Harper spent two years heading his own technology start-ups: BuyMyFace.com and Wriggle Ltd. As he begins his neuroscience PhD at UCL, Ross is living proof that you can take the boy out of the lab, but not the other way around. Between devising his latest crazy schemes, Ross makes an effort to eat (pizza), sleep (two pillows), and exercise (skiing/rugby/swimming). Follow him on Twitter @refharper.